An Elementary Study of Chemistry

An Elementary Study of
Chemistry, by

William McPherson and William Edwards Henderson This eBook is
for the use of anyone anywhere at no cost and with almost no
restrictions whatsoever. You may copy it, give it away or re-use it
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Title: An Elementary Study of Chemistry
Author: William McPherson William Edwards Henderson
Release Date: March 18, 2007 [EBook #20848]
Language: English
Character set encoding: ISO-8859-1
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ELEMENTARY STUDY OF CHEMISTRY ***

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AN ELEMENTARY
STUDY OF CHEMISTRY

BY
WILLIAM McPHERSON, PH.D.
PROFESSOR OF CHEMISTRY, OHIO STATE UNIVERSITY
AND
WILLIAM EDWARDS HENDERSON, PH.D.
ASSOCIATE PROFESSOR OF CHEMISTRY, OHIO STATE
UNIVERSITY
REVISED EDITION
GINN & COMPANY BOSTON * NEW YORK * CHICAGO *
LONDON
COPYRIGHT, 1905, 1906, BY WILLIAM MCPHERSON AND
WILLIAM E. HENDERSON
ALL RIGHTS RESERVED
The Athenæum Press GINN & COMPANY * PROPRIETORS *
BOSTON * U.S.A.

Transcriber's note:
For Text: A word surrounded by a cedilla such as ~this~ signifies that
the word is bolded in the text. A word surrounded by underscores like
this signifies the word is italics in the text. The italic and bold markup
for single italized letters (such as variables in equations) and "foreign"
abbreviations are deleted for easier reading.
For numbers and equations: Parentheses have been added to clarify
fractions. Underscores before bracketed numbers in equations denote a
subscript. Superscripts are designated with a caret and brackets, e.g.

11.1^{3} is 11.1 to the third power.
Appendix A and B have been moved to the end of the book. Minor
typos have been corrected.

PREFACE
In offering this book to teachers of elementary chemistry the authors
lay no claim to any great originality. It has been their aim to prepare a
text-book constructed along lines which have become recognized as
best suited to an elementary treatment of the subject. At the same time
they have made a consistent effort to make the text clear in outline,
simple in style and language, conservatively modern in point of view,
and thoroughly teachable.
The question as to what shall be included in an elementary text on
chemistry is perhaps the most perplexing one which an author must
answer. While an enthusiastic chemist with a broad understanding of
the science is very apt to go beyond the capacity of the elementary
student, the authors of this text, after an experience of many years,
cannot help believing that the tendency has been rather in the other
direction. In many texts no mention at all is made of fundamental laws
of chemical action because their complete presentation is quite beyond
the comprehension of the student, whereas in many cases it is possible
to present the essential features of these laws in a way that will be of
real assistance in the understanding of the science. For example, it is a
difficult matter to deduce the law of mass action in any very simple
way; yet the elementary student can readily comprehend that reactions
are reversible, and that the point of equilibrium depends upon, rather
simple conditions. The authors believe that it is worth while to present
such principles in even an elementary and partial manner because they
are of great assistance to the general student, and because they make a
foundation upon which the student who continues his studies to more
advanced courses can securely build.
The authors have no apologies to make for the extent to which they

have made use of the theory of electrolytic dissociation. It is inevitable
that in any rapidly developing science there will be differences of
opinion in regard to the value of certain theories. There can be no
question, however, that the outline of the theory of dissociation here
presented is in accord with the views of the very great majority of the
chemists of the present time. Moreover, its introduction to the extent to
which the authors have presented it simplifies rather than increases the
difficulties with which the development of the principles of the science
is attended.
The oxygen standard for atomic weights has been adopted throughout
the text. The International Committee, to which is assigned the duty of
yearly reporting a revised list of the atomic weights of the elements,
has adopted this standard for their report, and there is no longer any
authority for the older hydrogen standard. The authors do not believe
that the adoption of the oxygen standard introduces any real difficulties
in making perfectly clear the methods by which atomic weights are
calculated.
The problems appended to the various chapters have been chosen with
a view not only of fixing the principles developed in the text in the